package/quagga: add libxcrypt optional dependency

Fix the following build failure raised since bump of glibc to version
2.39 in commit b5680f53d60acf8ff6010082f873438a39bd5d97:

/home/autobuild/autobuild/instance-5/output-1/host/lib/gcc/nios2-buildroot-linux-gnu/12.3.0/../../../../nios2-buildroot-linux-gnu/bin/ld: ../lib/.libs/libzebra.so: undefined reference to `crypt'

Fixes: b5680f53d60acf8ff6010082f873438a39bd5d97
 - http://autobuild.buildroot.org/results/984572031cedd124f48b5a5bc5abe6096d22eaf3

Signed-off-by: Fabrice Fontaine <fontaine.fabrice@gmail.com>
Signed-off-by: Yann E. MORIN <yann.morin.1998@free.fr>

package/quagga/Config.in

@@ -1,6 +1,7 @@
 config BR2_PACKAGE_QUAGGA
 	bool "quagga"
 	depends on BR2_USE_MMU # fork()
+	select BR2_PACKAGE_LIBXCRYPT if BR2_TOOLCHAIN_USES_GLIBC
 	help
 	  Routing software suite, providing implementations of OSPFv2,
 	  OSPFv3 (IPv6), RIP v1 and v2, RIPng (IPv6) and BGPv4+.

package/quagga/quagga.mk

@@ -33,6 +33,10 @@ else
 QUAGGA_CONF_OPTS += --disable-capabilities
 endif
 
+ifeq ($(BR2_PACKAGE_LIBXCRYPT),y)
+QUAGGA_DEPENDENCIES += libxcrypt
+endif
+
 ifeq ($(BR2_PACKAGE_PROTOBUF_C),y)
 QUAGGA_CONF_OPTS += --enable-protobuf
 QUAGGA_DEPENDENCIES += protobuf-c